Coupling circuits



' Feb.12, 1929. 1,702,068

w. wuRsT COULING CIRCUITS Filed sept. 15. 1925 Faw/mzyerj /tecez Ver INVENTOR WALTER WU RST By (adm,

TORNEY Patented Feb. 12, 1929.

' UNITED STATES 1,702,068 PATENT OFFICE.

WALTER WURsr, E BERLIN, GERMANY, Assrenon. 'roeEsELLsoHaE'r :FR nnanr- LosE TELEGRArHIE M. B. H., 0F BERLIN, eERMAnr, A coRroRnrroN or GERMANY.

COUPLING CIRCUITS.

Application led September 15, 1925, Serial No. 56,419, and in Germany October 15, 1924.

The subject matter of this invention consists of a new mode of connection of instruments and apparatus used in high frequency telegraphy and telephony on long distance high potential transmission lines. The invention consists essentially in coupling the high frequency apparatus with the said line by way of a closed circuit tuned Yto the high frequency circuit and having a series inductor inserted in the high potential line. The transmission line is at the same time specially grounded by way of a high frequency slierting circuit. In this arrangement continuous, excellent, reliable and uniform transmission or guiding of the high frequency energy along the line as well as taking off therefrom of the energy under similarly favorable conditions is possible regardless of the condition of the networkor line system and regardless of whether the long distance lineis connected to the central station, to the switch house or Whether it is separated therefrom or grounded;

This is due to the simultaneous utilization of the short-circuiting circuit and furthermore the closed coupling circuit such as is used to carry out this invention cannot be detuned by changed conditions in the transnission line.

In the accompanying drawings, the idea underlying this invention is exemplified in two different forms of construction or arrangement.

Fig. l represents one embodiment of my invention.

Fig. 2 is a representation of an embodiment of my invention for use with a plurality of high frequency circuits.

According to the scheme shown in Fig. 1 an inductor 2 is inserted in line l, the said inductor constituting jointly with two high tension condensers 3, 3, and a variable coupler coil I a closed circuit which is tuned to the high frequency carrier wave. With coil 1- is inductively coupled a transmitting or receiving circuit indicated generally by 5. Between the coupling circuit and the separating switch 6, the line end is grounded for high frequency currents through the circuit 7 which includes a small capacity condenser and an induction coil. The central station 9 transmits power over bus-bar 8 an'd may be grounded by circuit l0 by which the protective grounding of the long-distance line is established whenever workmen are operating upon the same. In this instance, the central station equipment is indicated by a high potential transformer.

The different line system connections are as follows: Vith the switch h placed in position a, the line has a free end, and is grounded for high frequency currents by way of the circuit 7; if the line is directly grounded as with the switch 6 in position Z), the said shortcircuit is replaced by this ground connection, but the conditions so far as the high frequency energy is concerned are the same as previously described; when the line is finally connected to the bus-bar 8 by means of switch 6 being in position c, the circuit 7 and the total capacity of the central station represent the high frequency short-circuit path, so that under this condition no change can occur with reference to the high frequency energy.

The arrangement may be designed for multiplex operation with a plurality of carrier waves having different frequencies. In case of duplex operation with separate high frequency waves for transmitting and receiving, the connection is so chosen that both the coupling circuit as well as the short-circuiting circuit are arranged in a two-wave manner. An illustration of such an arrangement is depicted by Fig. 2.

In Fig. 2 the coupling circuit is divided into two parallel coupling branches with the coupler coils 4 and 4b, respectively, for coupling with the transmitter and receiver 5a and 5b, respectively. Each branch contains a block 11 and 1lb, respectively, for blocking the frequency of the other branch, and a tuning means 12a and 12b, respectively. The short-circuiti'ng circuit is given a similar parallel construction in the two branches 7 a and 7 b. The operation of this circuit can be readily understood from the description of the circuit described in'Fig. l.

Having described my invention, I desire to secure by Letters Patent t-he following:

l. The combination of a high tension transmission circuit with a high frequency circuit kand means for coupling togetherthe two circuits, said high tension circuit including a coupling inductor to which said coupling means, consisting of a closed circuit timed to the high frequency, is connected.

2. In combination, a high tension transmission circuit having a coupling inductor therein, a high frequency circuit, and means for coupling the two circuits together comprisllO ing a pair of high potential condensers connected to the ends of the coupling inductor.

3. In combination, high tension equipment, a high tension transmission circuit connected thereto, a high frequency circuit, means for coupling the two circuits together, and a grounded high frequency short circuit connected to the high tension circuit between the coupling means and all of the high tension equipment.

il. ln combination, a high tension transmission line having a series inductor near Aone end, a high frequency circuit, means for coupling the twoV circuits together including a pair of high potential condensers connected to said inductor, and a grounded high frequency short-circuiting circuit connected between said inductor and the end of said transmission line. Y

5. ln combination, power equipment, a power transmission line connected thereto, a high frequency circuit, means for coupling the circuitto the line including an inductor in the line, a pair of high potential condensers connected thereto, and a coupling coil forminga circuit tuned to the high frequency, and a grounded high frequency short-circuiting` circuit connected to the power line between said inductor and the power equipment.

6. kThe combination with a power transmission line and high frequency communication apparatus .of means to couple the high frequency communication apparatus to the power line comprising an inductor inserted in the power line, a coil coupled tothe high frequency apparatus, and two high potential Vcondensers for serially connecting the inductor and the coil, said series combination being tuned to the working high frequency.

7. The combination with a power transmission line and a plurality of carrier current communication means operating at diilerent carrier frequencies of au arrangement for coupling the plurality of connnunication means to the power line comprising an inductor inserted in the power line, two high 'potential condcnsers connected to the ends of the inductor, and a plurality of parallel paths connected between the condensers each of which includes a coil for coupling with one of said communication means and each of which, in series with the ind uctor and the two condensers, forms a circuit tuned to the working frequency of the communication means to which it is coupled.

8. An arrangement according to claim 7 in which each of the parallel paths includes means to obstruct a working frequency other than its own.

9. An arrangement for carrier communication at a plurality of frequencies on a power line comprising power equipment, a power line connected thereto, communication appuratus operating with a plurality of working frequencies, means to couple said apparatus to said power line, and a circuit which forms a grounded short circuit for each of the working frequencies connected to the power line between the coupling means and the power equipment.

"WALTER VVURSI.

EJRTFCATE F CRRECTN.

Patem No. LTS. Granted February l2, 1929, to

WALTER WURST,

It is hereby certified that eare appears ehe pimed speeifieation of he above numbered patent requiing Correction as folewe: Page E., lines 64 amd 65, between the words shert" and "cireu" iseft me wer efeutieg"; and hat he said Lettes Paeil sheud be read wih this erreeon heren that the same may conform to he ieeord the cese in he Patem 'Hiee.

Signe-d and sealed this 11th of June, A.v D. W29.

M. l. Moore, (Seal) Acting Ccmmssiener ef Patents. 

